A conventional lamp socket typically consists of a case, an electric bulb cap, and spring-loaded electric contacts. The electric bulb cap is a cylindrical sleeve. The sleeve has a helical groove or a bayonet retainer. The electric bulb is installed into the lamp socket with a helical groove or a bayonet retainer with an application of effort. The effort ensures the spring-loaded contacts of the lamp socket press against the electric bulb contacts. It also takes an effort to remove a faulty (burned-out) electric bulb. Due to the widespread use of lighting devices, the labor-intensive process of installing and replacing electric bulbs causes substantial financial losses. It is especially difficult to remove an electric bulb with a broken bulb glass, since it is difficult to apply the required force without holding the bulb. A risk of injury is involved. The reliability of electrical contact is ensured by the elastic properties of the conductor. In case of non-elastic deformation of contacts due to mechanical or thermal impacts, the risk of a lighting device malfunction increases. This is a frequent occurrence during the operation of lighting devices. Sometimes an electric bulb is installed with the power connected to make sure the lighting device is functional. This raises the risk of electrocution.
Prior art discloses a lamp socket (Patent RU 2 296 402 C1) that has been chosen as a prototype (the closest related art device) for this invention. It consists of a case, electrical contacts within the case, and an electric bulb cap. The electric bulb cap is made in the form of a clamp with a spring, an arm, a retainer, and a retainer release button. The clamp consists of a movable part and an immovable part. When an electric bulb is places into the lamp socket, the electric bulb base freely enters the retainer. The bottom contact of the electric bulb depresses the contact of the lamp socket and shifts the retainer release button. The retainer releases the arm. Under the influence of the spring, the arm presses the movable part of the clamp together with the retainer contact tip to the electric bulb base, clamping the base. The retainer contact is pressed against the electric bulb contact by means of the retainer release button. The retainer contact is pressed against the electric bulb base by means of the spring via the arm and the movable part of the clamp. To extract the electric bulb, one has to press the end of the arm in the direction of the glass bulb. When this is done, the arm compresses the spring, shifts the movable part of the electric bulb base clamp, and releases the electric bulb base from the retainer. This lamp socket design enables easy installation and replacement of electric bulbs while ensuring reliable contact with the electric bulb. Yet, the design described here is rather complex compared to a standard lamp socket. The arm releasing the electric bulb base from the clamp is located close to the electric bulb, so there is a risk of sustaining burns if the electric bulb is still hot.